Magnetic connection



1950 J. P. DOLAN 2,526,206

mama-rm coumac'non Filed Oct. 16, 1948 F1 5 4 ZIVENTOR.

Patented Oct. 17, 1950 UNITED STATES PATENT orrica James P. Dolan,Springfield, Mass.

Application October 16, 1948, Serial No. 54,930

1 Claim.

My invention relates to improvements in a device for releasablyconnecting electrical circuits and isdirected more'particularly totheprovision of adevicefor releasably connecting an electrical circuitand to an improvement in the means for maintaining a circuit such as acircuit which is closed under normal operating conditions.

With the above primary object in view, it is another object of myinvention to provide a construction of the'alo'ove described characterwhich is relatively simple and compact in accordance with the demandsand desires of the purchasing public as well as of the manufacturersthereof and which is not only attractive in its appearance and practicalin its value but also reliable in its operati'onand thoroughlyeflicient'in its use.

It is common practice to employ closed electrical circuits in connectionwith such'systems as burglar 'and fire alarms the same being so arrangedthat upon rupture of the circuit the alarm is activated.

In connection with burglar alarm systems particularly, it is a commonpractice to locate wiring adjacent door and window openings and the likeso that the wiring, which is usually included in a closed alarm circuit,is disrupted upon unlawful movement or breakage of a window, door or thelike to thereby bring about operation of the alarm..

According to the novel features of this invention a connecting device isprovided which is adapted for releasably connecting a circuit and whileadapted for many and various other uses it is arranged for use as aconnection as in a closed circuit and is operable by various means toopen 'a circuit. "Ihe novel construction of the invention includesiniabroad way a combined or integral electrical conductor or contact elementand a magnetized element arranged in :such a manner that contactelements may be connected in a circuit and held in contactingrelationship b the attraction of the magnetized elements one to theother.

The magnetized elements will be of such a nature as to hold the contactelements together sufiiciently for an efiicient electrical contact undernormal conditions yet when subjected to abnormal conditions the magneticattraction is disrupted so that the electrical contact elements areseparated.

While the device of the invention is useful in a. close circuit it isequally useful for a temporary connection in wiring systems.

Other prime objects of my invention include;

first, the provision of a simplified construction and arrangement -of adevice for releasably connecting an electrical circuit which is strong,durable and compact in its structure and is distinctive in itsappearance; second, the securement of a higher degree of accuracy in themanner of work performed therewith than has heretofore been possiblewith prior devices known in the art; third, the attainment of a higherdegree of speed of construction and assembly of the-device due to itssimplification in design and its unique composition of parts; fourth-theattainment of a flexibility or a capability of adjustment by which alarge variety of workcan-rbe produced by means of the same device;fifth, the achievement of a greater ease in adjustment and repairs;sixth, the provision of an improved signalling device which may be-mademore economical and with fewer operations in the manufacture of itsparts, as well as in the assembly'of the same, than prior devices knownin the art; and seventh, the provision of a construction which may bereadily installed with respect to doors, windows and the like.

These objects I accomplish by means of such structure and relativearrangement of parts thereof, as will fully appear by a perusal of thedescription below and by various specific features whichwillbehereinafter set forth.

To the above cited and otherends-and with the foregoing and variousother novel features and advantages and other objects of my invention aswill become more readily apparent as the description proceeds, myinvention consists in certain novel featuresof construction and in thecombination and arrangement of parts aswill be hereinafter moreparticularly pointed out in the claim hereunto annexed and more fullydescribed and referred to in connection with the accompanying drawingswherein:

"Fig. l'is a plan view of a circuit connector device embodying the novelfeatures ofthe invention,

Fig. 2 is a side elevational view showing a pair of the devices of Fig.1 in circuit connecting relationship,

Fig. 3 is a longitudinal sectional view through the connecting device ofFig. 1, and

Fig. 4 is a diagrammatic elevational view to explain how the device maybe used.

In the above mentioned drawings annexed hereto and forming a part ofthis specification, I have shown but one embodiment of my inventionwhich is deemed preferable, but it is to be understood that changes andmodifications may I 3 be made within the scope of the appended claimwithout departing from the spirit of the invention.

Referring now to the different drawings more in detail, in which similarcharacters of reference indicate corresponding parts in all the figuresand referring more particularly to the preferred form of my inventionselected for illustrative purposes, I have shown a device 2 of theinvention which includes a contact element 4 suitable for electricalconduction and may consist of brass, copper or the like and said elementmay have a lug 6 for connecting in a circuit.

A magnetized element 8 is associated with the element 4 and this may beaccomplished in various ways.

In the form of the invention shown a sheath I is provided in which theelement 8 is disposed and the sheath may be made from conductingmaterial and provided with flanges I2 which are secured to the element4. In this way the elements 4 and 8 are associated to provide acomposite structure.

It will be understood that the elements 4 and 8 may take other forms andcome within the limits of the invention which in its broad aspectincludes one element made from a conducting material and the otherformed from a magnetized material.

In Fig. 2 a pair of devices are shown. Electrical elements 4 arereleasably held in contacting relation by the magnetized elements 8associated therewith. With the elements 4 connected in a circuit, areleasable electrical connection is accomplished which may be disruptedby abnormal forces applied to the connection or to the wiring extendingtherefrom.

The sheath H) is preferably made of brass and offers a better contactsurface and prevents rusting of the element 8.

As has been stated the device is not only adapted for temporaryconnection in a circuit but may be employed in a normally closed circuitwhere it is desired that the circuit be opened by the application ofunlawful forces.

As an instance of its use, one of the devices may be secured to a dooror window sash and another to the adjacent frame so as to be in contactwhen the door or window is in one position and separated when the dooror window is moved.

As another illustration of its use, a pair of the connectors 2 may besecured to opposite sides 14 of a door frame and connected in a circuit.Devices indicated by 2 having a, connection 16 therebetween are held incontact with the contacts 2. The connection [6 extends across the dooropening and completes the circuit.

Should door [8 be swung open the connection will readily be engaged byone passing through the door opening and one or both of the devices 2separated from its companion device 2 and break the circuit.

In the case of burglar alarm work, the contacts have to be good so as toreduce to a minimum false alarms. Contacts must break easily and yetcannot be too secure. The device of my invention meets theserequirements in every detail.

Further, my invention has the advantage that the pull or push may be inany direction, the contact surfaces being such that same is facilitated.

It may be desired that the non-magnetic contact and the magnetizedelements be insulated from one another so that the latter is not in theelectrical circuit while at the same time the elements are associatedfor the purpose of the invention. This may be accomplished by any of thewell known insulating materials.

The invention may be embodied in other specific forms without departingfrom the essential characteristics thereof. Hence, the presentembodiments are therefore to be considered in all respects merely asbeing illustrative and not as being restrictive, the scope of theinvention being indicated by the appended claim rather than by theforegoing description, and all modifications and variations as fallwithin the meaning and purview and range of equivalency of the appendedclaim are therefore intended to be embraced therein.

What it is desired to claim and secure by Letters Patent of the UnitedStates is:

The combination of a door frame or the like with rupturable circuitmeans thereacross comprising, fixed contact members fixed to oppositesides of said door frame each including a magnetized member and a metalsheath therearound adapted to conduct electrical current, and a pair ofseparate contact members each including a metal sheathed magnetizedmember adapted to conduct electrical current and an elongated electricalconductor connecting said separate contact members, said separatecontact members held in contact with said fixed contact members by themagnetized members with the elongated conductor extending across thedoor opening whereby a circuit is ruptured by separation of either oneof said separate contact members with its corresponding fixed contactmember.

JAMES P. DOLAN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,709,716 Fielder Apr. 16, 19292,170,287 Kinnebrew Aug. 22, 1939 2,204,396 Barnes June 11, 19402,389,298 Ellis Nov. 20, 1945

